CVE-2026-40886

Argo Workflows: Unchecked annotation parsing in pod informer crashes Argo Workflows controller

Argo Workflows is an open source container-native workflow engine for orchestrating parallel jobs on Kubernetes. From 3.6.5 to 4.0.4, an unchecked array index in the pod informer's podGCFromPod() function causes a controller-wide panic when a workflow pod carries a malformed workflows.argoproj.io/pod-gc-strategy annotation. Because the panic occurs inside an informer goroutine (outside the controller's recover() scope), it crashes the entire controller process. The poisoned pod persists across restarts, causing a crash loop that halts all workflow processing until the pod is manually deleted. This vulnerability is fixed in 4.0.5 and 3.7.14.

Affected

argoproj · argo-workflows

CVSS v3.1 CNA

7.7 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

EPSS

0.59% chance of exploitation in the next 30 days, 47th percentile

Published

2026-04-23

Updated

2026-07-15

Proof-of-concept exploits (1)

• advisories/GHSA-5jv8-h7qh-rf5p

Security advisories

• argoproj/argo-workflows/security/advisories/GHSA-5jv8-h7qh-rf5p

References

• CVE Record
• NVD entry